From 87b87d7b5d6159fb7b0259c1021f4af9dd919c56 Mon Sep 17 00:00:00 2001
From: xuxin <840198532@qq.com>
Date: Sun, 1 Feb 2026 10:34:45 +0800
Subject: [PATCH] =?UTF-8?q?=E8=BF=9B=E9=98=B6day03-=E5=AF=B9=E8=B1=A1?=
 =?UTF-8?q?=E7=9A=84=E5=93=88=E5=B8=8C=E5=80=BC(hashCode())?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../src/com/inmind/set02/HashDemo08.java      | 37 +++++++++++++++++++
 .../src/com/inmind/set02/Student.java         | 29 +++++++++++++++
 2 files changed, 66 insertions(+)
 create mode 100644 javaSE-day03/src/com/inmind/set02/HashDemo08.java
 create mode 100644 javaSE-day03/src/com/inmind/set02/Student.java

diff --git a/javaSE-day03/src/com/inmind/set02/HashDemo08.java b/javaSE-day03/src/com/inmind/set02/HashDemo08.java
new file mode 100644
index 0000000..7f883e9
--- /dev/null
+++ b/javaSE-day03/src/com/inmind/set02/HashDemo08.java
@@ -0,0 +1,37 @@
+package com.inmind.set02;
+/*
+1.什么是哈希值??
+    哈希值就是一个对象的特征码,使用一个十进制int值来表示的.int的值是有限的，但是对象是无限的(不同的对象的哈希值可能相同)
+    注意：不同的对象的哈希值可能相同！！！
+
+ 2.如何获取一个对象的哈希值呢??
+    Object类中有一个方法hashCode方法可以获取
+    int hashCode() 返回对象的哈希码值。
+
+    Object类的hashCode的源码:
+    public native int hashCode();//通过真正的地址值使用哈希算法返回的一个int值
+
+3.我们发现每个对象的哈希值默认是通过地址来获取,这样没有意义.我们在实际开发中
+    希望拥有相同内容的同一类对象的哈希值的一致.所以子类重写hashcode.我们可以模拟一个
+    已经重写过hashcode,并且经常使用的类.得出一个结论,String的哈希值跟它的内容有关,那么
+    自定义类自动重写hashcode那么也应该跟类的内容(属性)有关
+
+ */
+public class HashDemo08 {
+    public static void main(String[] args) {
+        //创建2个内容相同的学生对象
+        Student s1 = new Student("刘备", 18);
+        Student s2 = new Student("刘备", 18);
+        //获取2个对象的哈希值
+        int hash = s1.hashCode();
+        System.out.println(hash);
+        System.out.println(s1);
+        System.out.println(s2.hashCode());
+
+        String str1 = "abc";
+        String str2 = new String("abc");
+
+        System.out.println(str1.hashCode());
+        System.out.println(str2.hashCode());
+    }
+}
diff --git a/javaSE-day03/src/com/inmind/set02/Student.java b/javaSE-day03/src/com/inmind/set02/Student.java
new file mode 100644
index 0000000..dcb1a2c
--- /dev/null
+++ b/javaSE-day03/src/com/inmind/set02/Student.java
@@ -0,0 +1,29 @@
+package com.inmind.set02;
+
+import java.util.Objects;
+
+public class Student {
+    String name;
+    int age;
+
+    public Student(String name, int age) {
+        this.name = name;
+        this.age = age;
+    }
+
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == null || getClass() != o.getClass()) return false;
+
+        Student student = (Student) o;
+        return age == student.age && name.equals(student.name);
+    }
+
+    @Override
+    public int hashCode() {
+        int result = name.hashCode();
+        result = 31 * result + age;
+        return result;
+    }
+}